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721.
Summary A new species of genusPeyronellaea, P. indianensis sp. nov., has been described. Its isolation from the soil is the first record to science. It differs from previously recorded five species parasitizing various host plants. As it is isolated on a filter paper buried in the soil, it is a cellulose decomposing fungus 相似文献
722.
A S Deshpande K K Surendranathan P M Nair 《Indian journal of biochemistry & biophysics》1991,28(3):193-197
The change in activity of cinnamic acid 4-hydroxylase (CA4H) in potato parenchyma tissue exposed to various conditions has been examined. Maximum induction of CA4H activity was obtained at 18 hr of incubation. Though CA4H induction can occur in dark, over 100% increase in enzyme activity was obtained on exposure of the tissue to light. Actinomycin D and cycloheximide inhibited the induction process. Mn2+, though known to cause an induction of CA4H in Jerusalem Artichoke, strongly inhibited potato CA4H induction. Dithiothreitol enhanced the CA4H activity due to either activation or protection of the enzyme. CA4H induction was significantly regulated at very low concentrations of trans-cinnamate and paracoumarate. 相似文献
723.
A strain of Rhizopus stolonifer produced high levels of extracellular ribonuclease (RNase) when grown on YPG (yeast extract, peptone, glucose) medium. Influence
of various medium components on the production of extracellular RNase activity showed that divalent metal ions had a marked
effect on growth and enzyme production. Maximum enzyme activity (3000 U/ml) was obtained in 5 days when the culture was grown
in YPG medium containing Mg2+ (12 mM), Mn2+, and Fe2+ (2 ppm each). Inorganic phosphate, however, repressed enzyme production. Antibodies raised against the purified extracellular
RNase were then used to establish the relationship between intra- and extracellular enzymes. 相似文献
724.
Data on biomass, production and metabolism of the biota, gathered during many years in the Rybinsk Reservoir, USSR, were used to calculate functional interconnections between separate components of the ecosystem, neglecting fluctuations of biomass and postulating a stationary state of the system.A matrix of interconnections was constructed and the influence of an increase or decrease of the biomass of one element upon all other elements of the ecosystem was calculated and discussed. 相似文献
725.
Summary Catalase in yeast cells is rendered thermolabile on permeabilization using organic solvents or any process of immobilization that eventually permeabilizes the cells. A stable immobilized catalase preparation can be obtained only if yeast cells are immobilized in an intact or viable form. 相似文献
726.
727.
Christopher D. Wiley Rishi Sharma Sonnet S. Davis Jose Alberto Lopez-Dominguez Kylie P. Mitchell Samantha Wiley Fatouma Alimirah Dong Eun Kim Therese Payne Andrew Rosko Eliezer Aimontche Sharvari M. Deshpande Francesco Neri Chisaka Kuehnemann Marco Demaria Arvind Ramanathan Judith Campisi 《Cell metabolism》2021,33(6):1124-1136.e5
728.
729.
730.
pH-Dependence of hydrolytic activity of trypsin has been studied in cationic reverse micellar system of cetyltrimethylammonium bromide (CTAB) in (50% v/v) chloroform/isooctane using a positively charged substrate Nα-benzoyl-L-arginine ethyl ester (BAEE). The pH of the medium was varied from 4.0 to 8.5 with addition of 0.025 M citrate-phosphate buffer containing 1 mM CaCl2. Optimum pH for maximum enzyme activity, pHopt in reverse micelles is found to be similar to that observed in bulk aqueous solution (8.0–8.5). However, changes in activity of trypsin (kcat) as a function of water content W0 (W0 = [H2O]/[CTAB]) in reverse micelles are found to be pH dependent. At low pH (4.0) and low water content (W0 = 5) the enzyme is more active in reverse micelles than in bulk aqueous solution by a factor of 2. This ‘superactivity’ is lost at higher W0 values and the kcat in reverse micelles is found to be similar to that observed in aqueous bulk. At pH 5, the enzyme activity is found to be independent of W0 while at pH 6.0–6.5 the enzyme activity is low at W0 5 and increases with water content to a constant value which is still 50% lower than that in aqueous buffer. Above pH 7, the Wo-activity profile becomes distinctly bell shaped with W0 optimum around 10–15. The enzyme activity at optimum W0 is close to that observed in aqueous bulk. 相似文献